STUDY TREATMENTS: The study will start with a screening visit (day -21 to day 0) after obtaining informed consent of the patient. Patients screened for recruitment of patient 5 must give their consent for a baseline biopsy (tumor excision) and optional for a follow-up biopsy (after end of week 3 of cycle 2; tumor excision). Patients, who qualify for participation and are willing to participate, will receive in this period a central venous catheter for the conduction of the extracorporeal OncoSorb® therapy. During the treatment period all patients will receive OncoSorb® treatments consisting of daily immune adsorption treatment procedures 5 days per week for 3 weeks, followed by a resting period of one week. Due to safety reasons all patients will be hospitalized at the NCT during the first week of OncoSorb® treatment. Since currently no information exists about the counterregulation kinetics of sTNF-R1, sTNF-R2 and sIL-2Rα upon OnsoSorb® treatment, the collection of pharmacokinetic (PK) data is planned for the first 3 recruited patients. Blood samples for PK measurements of these patients will be taken between day 4 and 5 of the first treatment cycle under hospitalized conditions. PK data will be essential for designing an optimized treatment schedule (potential reduction of both frequency and apheresis time) of subsequent patients on trial. The schedule of the first 3 patients constitutes a one monthly treatment cycle. For the 2 remaining patients of this study the treatment plan will be re-designed according to the PK data obtained from the first 3 patients on treatment. The efficacy evaluation will be carried out 8 weeks after beginning of treatment. Patients with progression of disease may be withdrawn from OncoSorb® treatment. Patients with complete response (CR), partial response (PR) or stable disease (SD) will be offered to continue OncoSorb® treatments until disease progression. In this case efficacy evaluation (CT scans) will be performed every 8 weeks.